The Energy Department wants to pay companies to make more environmentally friendly solar panels

In June, US solar manufacturer Qcells became the second company in the world to register its solar modules with EPEAT, a labeling system that sets sustainability standards for electronics manufacturers. In doing so, the company triggered an obscure regulation that requires federal agencies to purchase EPEAT-certified solar modules. For example, if NASA wants to build a solar farm to power a research facility, it must now purchase panels that meet EPEAT's strict sustainability requirements – including a unique limit on carbon emissions associated with solar production.

There's just one problem: Although EPEAT launched its solar standards in 2019, there are only six EPEAT-registered solar modules on the global market to date. And there are currently no EPEAT-registered solar inverters, devices that convert the direct current generated by a solar panel into alternating current that is used by the grid. This leaves neither the federal government nor anyone else who wants to buy sustainably produced solar systems many options.

That's why the Department of Energy (DOE) launched a new award in October that offers up to $450,000 to U.S. solar panel and inverter manufacturers that achieve EPEAT certification for their products. As a new wave of domestic solar production gets underway, the DOE hopes the award will ensure companies use efficient processes, sustainable materials, fair labor practices and low-carbon energy.

“The fact is that not all solar (products) are created equal in their production,” said Patty Dillon, vice president of the Global Electronics Council, the sustainable technology nonprofit that administers the EPEAT ecolabel.

Solar panels convert the sun's rays into a process that does not emit pollutants Greenhouse gaseswhich makes them indispensable for combating climate change. To reach net-zero emissions by 2050, the International Energy Agency estimates the world will need to add 630 gigawatts of new solar power annually by 2030 – up from the 135 gigawatts installed in 2020.

But some solar modules are more climate-friendly than others. Polysilicon, used to make the sunlight-harvesting cells in silicon panels, is produced in an energy-intensive process that often runs on fossil fuels. The frames that hold the solar panels together are made of aluminum, which is typically melted using coal-fired power in China. The manufacturing processes that turn these materials into a solar panel also require energy, which can lead to more emissions. On a global scale, the difference between solar panels made with clean energy and those made with fossil fuels could amount to tens of billions of tons of carbon pollution by the mid-21st century.

To minimize these emissions and other environmental challenges such as toxic chemical use and solar e-waste disposal, companies must take a close look at their supply chains and, in some cases, undertake difficult cleanups. The DOE's new award, Promoting Registration of Inverters and Modules with Ecolabel, or PRIME, encourages companies to do this by going through the EPEAT registration process.

“EPEAT certification allows companies to demonstrate how they have taken steps toward greener supply chains and manufacturing processes,” Becca Jones-Albertus, director of the Department of Energy’s Office of Solar Energy Technologies, told Grist.

Solar companies seeking EPEAT registration must meet a list of criteria covering four broad topics: climate change, sustainable resource use, hazardous chemicals and responsible supply chains. Depending on how many standards a manufacturer meets, they can receive an EPEAT Bronze, Silver or Gold award.

In addition, starting in June, EPEAT-registered solar manufacturers will be required to meet the industry's first criteria for embodied carbon, which is the emissions produced during the manufacture of a product. No more than 630 kilograms of CO2 may be emitted per kilowatt of electricity generated during the production of an EPEAT-registered solar module. According to Dillon, the limit represents about 25 percent less CO2 emissions than the global average. Solar modules that are below the “ultra low carbon” limit of 400 kilograms of CO2 per kilowatt of output receive the special EPEAT Climate+ award.

“This is basically top of the class,” Dillon said.

It is difficult to make a direct comparison with fossil fuel plants because most of their emissions come from operations rather than building infrastructure. However, other research has found that solar systems are significantly more climate friendly over their lifetime, emitting around 50 grams of CO2 per kilowatt hour of energy produced, compared to around 1,000 grams per kilowatt hour for coal.

Meeting EPEAT's requirements is not easy, which may explain why only two companies – QCells and Arizona-based First Solar – are currently listed on the registry. And only two solar modules manufactured by First Solar have received the Climate+ seal of eco-label. QCells, which makes two EPEAT-registered panels at a factory in Dalton, Georgia, spent about two years going through a “very extensive” certification process that collected data across the entire supply chain and subjected it to a third-party audit Head of corporate communications Debra DeShong told Grist.

“This is not an easy task,” DeShong said. “It requires resources and a will.”

Other companies might now be motivated to give it a try. The addition of QCells to the EPEAT registry in June activated the Federal Acquisition Regulation, which requires the federal government to purchase goods that meet standards set by the U.S. Environmental Protection Agency, except in certain cases where doing so is impractical. In the case of solar modules, these are EPEAT-registered products. An additional incentive is the DOE's PRIME Award, which provides U.S. solar manufacturers $50,000 to begin the registration process and up to $100,000 per product for up to four products that complete it. Jones-Albertus told Grist that the price was intended to “roughly offset the cost of collecting all the data and the registration process.”

Solar companies “have told us they are interested in EPEAT certification but have not yet achieved it,” Jones-Albertus said. “We hope to incentivize companies to go through the EPEAT registration process sooner.”

Companies looking deep into their supply chains for the first time may find that they need to make some changes to meet EPEAT registration requirements. To reduce the carbon footprint of its panels, a solar manufacturer may need to switch to a low-carbon polysilicon supplier. (QCells, for example, buys polysilicon from a plant in Washington state that produces the material using hydroelectric power.) Or the company decides to replace new aluminum frames made abroad with recycled steel frames made domestically by Origami Solar, one change , which can lead to cost savings CO2 emissions are tied to the frame by more than 90 percent. To meet EPEAT's optional recycled content criteria, a manufacturer might choose to purchase recycled sheet glass from a company like SolarCycle.

Implementing such changes in the manufacturing supply chain requires time and money beyond what the new DOE award will provide. But Dillon of the Global Electronics Council is optimistic that more companies will begin registering their products with EPEAT now that federal buyers are required to do so.

Erik Petersen, chief strategy officer at Origami Solar, believes the Biden administration's push for clean domestic manufacturing, coupled with growing consumer interest in supply chain transparency, will encourage more U.S. solar companies to ensure that their products meet high sustainability standards.

“The exciting thing is that all of these forces are coming together at the same time,” Petersen told Grist. “It really incentivizes the industry to do the right things.”